This invention relates to devices for projecting the eyes from unwanted light and, particularly, to light absorbing visors for shielding the viewer's eyes from light emanating from a video display terminal and for shielding the terminal from ambient light.
Visual display devices, including video display terminals [VDT], monitors, television screens and the like, are quite frequently placed in environments with little regard for the ambient light sources which place extraneous light on the screen. These light sources include overhead lights, windows, desk lamps, and even reflected light from desk tops, walls and ceilings. The extraneous light frequently gives rise to eye strain and fatigue in persons using the video display terminals due to the resultant reduction in contrast and clarity of the information displayed on the screen. It is known that light reflecting from the VDT screen causes a measure of eye strain and in environments where people use computers throughout the work day, they are subject to various forms of stress, including fatigue, headaches, blurred vision, and decreased perception information. This results in increased errors in the data being processed and psychological depression in the individuals. Such conditions have been found in processing operations, including bank check processing facilities, credit card processing facilities, and the like.
Workers in the field have tried to reduce the glare upon the VDT by making shades or other similar devices from cardboard or paper and taping the shades to the cabinet containing the video display tube. U.S. Pat. No. 4,633,324 shows an adjustable shield which conforms to the side walls of the VDT cabinet and projects outwardly therefrom for shading the screen area. Other workers have devised transparent filters that fit over the VDT screen itself, resulting in reduced clarity of the information display on the screen and sometime requiring an increase of the operational brightness level of the VTD.
The prior art shields or hoods for computer terminals had several common features. Basically, the prior art products were fabricated from sheet plastic or injection molded, being offered in a fixed or restricted range of sizes. Those constructions were generally rectilinear in form so as to closely follow the top and sides of the VDT to which they were attached. The generally rectilinear form gave inside surfaces which were flat and parallel, and tended to support reflective standing waves from the non-light absorbing flat surfaces. The condition did not ameliorate eye fatigue in that the hood or visor had minimal, if any, light absorbing qualities.